The field of the invention pertains to telephones and in particular telephones with modular plug and jack connections. For a number of years the familiar four prong plug and jack telephone connections have been in use in North America and many homes have been wired for such units. More recently modular plugs on the cords and jacks in the telephone units and headpieces have come into use. The new plugs and jacks are significantly smaller and more convenient.
U.S. Pat. Nos. 3,876,273, 4,047,787 and 4,050,768 disclose modern modular block and extension cord devices for electric and telephone connections. In particular U.S. Pat. No. 4,050,768 discloses an interconnector for adapting existing telephone wall outlets to the modern modular plug and jack connection. U.S. Pat. No. 4,047,787 discloses an extension cord for modular plug and jack telephones that permits two telephones to be connected in parallel to one jack. None of the above modular block and extension cord devices, however, permit a wide combination of telephones, handsets and recording devices to be interconnected for multiparty use as desired.